For me the biggest problem with SO is that it's hard to get answers to advanced questions in some areas. Not a lot of people could answer the question in the first place, because it's about some obscure and rarely encountered problem, and these experts are constantly spammed with basic questions from inexperienced programmers. Though it depends on the area you're interested in - I've got almost no answers to advanced Rails-related questions and got pretty good responses to Scala-related stuff I'm interested in (but maybe it's because Scala questions were about more basic stuff)